A quick question about current loops

Thread starter a9211l
Start date Oct 14, 2007
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Current Loops

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The Biot-Savart equation effectively calculates the magnetic field inside a current loop. To determine the magnetic field outside the loop, particularly off-axis, a Legendre polynomial expansion of the magnetic scalar potential is required. This approach involves complex mathematical techniques, including elliptic integrals. For practical applications and further exploration, a specific resource is provided in the discussion. Understanding these concepts is crucial for accurately modeling magnetic fields in various scenarios.

Oct 14, 2007

a9211l

Applying the Biot-Savart eq'n for inside a current loop is pretty simple to find the magnetic field inside a current loop.

But how would one find the magnetic field outside of one?

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Oct 16, 2007

Meir Achuz

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On the axis, it is fairly simple.
Off axis, you need a Legendre polynomial expansion of the magnetic scalar potential.

Oct 19, 2007

robphy

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Elliptic Integrals:
e.g.,
http://www.netdenizen.com/emagnettest/offaxis/?offaxisloop

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